"Mark all items as read" doesn't work after changing source of feed
STEPS TO REPRODUCE
1. Edit an existing feed.
2. Change the source URL for the feed.
3. Do "fetch feed".
4. See new unread items appear.
5. Do "mark all as read" on feed.
Items in feed do not change from unread to read. If you quit and re-launch Akregator, then "mark all as read" will work on that feed.
Items in feed should change from unread to read.
In fact, even moving up and down through items in feed does not change them from unread to read, until after you restart the application.